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1.
Plant Cell ; 35(11): 4133-4154, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37542517

RESUMO

Phytohormones play indispensable roles in plant growth and development. However, the molecular mechanisms underlying phytohormone-mediated regulation of fiber secondary cell wall (SCW) formation in cotton (Gossypium hirsutum) remain largely underexplored. Here, we provide mechanistic evidence for functional interplay between the APETALA2/ethylene response factor (AP2/ERF) transcription factor GhERF108 and auxin response factors GhARF7-1 and GhARF7-2 in dictating the ethylene-auxin signaling crosstalk that regulates fiber SCW biosynthesis. Specifically, in vitro cotton ovule culture revealed that ethylene and auxin promote fiber SCW deposition. GhERF108 RNA interference (RNAi) cotton displayed remarkably reduced cell wall thickness compared with controls. GhERF108 interacted with GhARF7-1 and GhARF7-2 to enhance the activation of the MYB transcription factor gene GhMYBL1 (MYB domain-like protein 1) in fibers. GhARF7-1 and GhARF7-2 respond to auxin signals that promote fiber SCW thickening. GhMYBL1 RNAi and GhARF7-1 and GhARF7-2 virus-induced gene silencing (VIGS) cotton displayed similar defects in fiber SCW formation as GhERF108 RNAi cotton. Moreover, the ethylene and auxin responses were reduced in GhMYBL1 RNAi plants. GhMYBL1 directly binds to the promoters of GhCesA4-1, GhCesA4-2, and GhCesA8-1 and activates their expression to promote cellulose biosynthesis, thereby boosting fiber SCW formation. Collectively, our findings demonstrate that the collaboration between GhERF108 and GhARF7-1 or GhARF7-2 establishes ethylene-auxin signaling crosstalk to activate GhMYBL1, ultimately leading to the activation of fiber SCW biosynthesis.


Assuntos
Fibra de Algodão , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ácidos Indolacéticos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Gossypium/genética , Gossypium/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Etilenos/metabolismo , Parede Celular/metabolismo
2.
Circulation ; 150(13): 981-993, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39166327

RESUMO

BACKGROUND: Colchicine has been approved to reduce cardiovascular risk in patients with coronary heart disease on the basis of its potential benefits demonstrated in the COLCOT (Colchicine Cardiovascular Outcomes Trial) and LoDoCo2 (Low-Dose Colchicine 2) studies. Nevertheless, there are limited data available about the specific impact of colchicine on coronary plaques. METHODS: This was a prospective, single-center, randomized, double-blind clinical trial. From May 3, 2021, until August 31, 2022, a total of 128 patients with acute coronary syndrome aged 18 to 80 years with lipid-rich plaque (lipid pool arc >90°) detected by optical coherence tomography were included. The subjects were randomly assigned in a 1:1 ratio to receive either colchicine (0.5 mg once daily) or placebo for 12 months. The primary end point was the change in the minimal fibrous cap thickness from baseline to the 12-month follow-up. RESULTS: Among 128 patients, 52 in the colchicine group and 52 in the placebo group completed the study. The mean age of the 128 patients was 58.0±9.8 years, and 25.0% were female. Compared with placebo, colchicine therapy significantly increased the minimal fibrous cap thickness (51.9 [95% CI, 32.8 to 71.0] µm versus 87.2 [95% CI, 69.9 to 104.5] µm; difference, 34.2 [95% CI, 9.7 to 58.6] µm; P=0.006), and reduced average lipid arc (-25.2° [95% CI, -30.6° to -19.9°] versus -35.7° [95% CI, -40.5° to -30.8°]; difference, -10.5° [95% CI, -17.7° to -3.4°]; P=0.004), mean angular extension of macrophages (-8.9° [95% CI, -13.3° to -4.6°] versus -14.0° [95% CI, -18.0° to -10.0°]; difference, -6.0° [95% CI, -11.8° to -0.2°]; P=0.044), high-sensitivity C-reactive protein level (geometric mean ratio, 0.6 [95% CI, 0.4 to 1.0] versus 0.3 [95% CI, 0.2 to 0.5]; difference, 0.5 [95% CI, 0.3 to 1.0]; P=0.046), interleukin-6 level (geometric mean ratio, 0.8 [95% CI, 0.6 to 1.1] versus 0.5 [95% CI, 0.4 to 0.7]; difference, 0.6 [95% CI, 0.4 to 0.9]; P=0.025), and myeloperoxidase level (geometric mean ratio, 1.0 [95% CI, 0.8 to 1.2] versus 0.8 [95% CI, 0.7 to 0.9]; difference, 0.8 [95% CI, 0.6 to 1.0]; P=0.047). CONCLUSIONS: Our findings suggested that colchicine resulted in favorable effects on coronary plaque stabilization at optical coherence tomography in patients with acute coronary syndrome. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04848857.


Assuntos
Síndrome Coronariana Aguda , Colchicina , Placa Aterosclerótica , Tomografia de Coerência Óptica , Humanos , Colchicina/uso terapêutico , Feminino , Síndrome Coronariana Aguda/tratamento farmacológico , Síndrome Coronariana Aguda/diagnóstico por imagem , Pessoa de Meia-Idade , Masculino , Placa Aterosclerótica/tratamento farmacológico , Placa Aterosclerótica/diagnóstico por imagem , Método Duplo-Cego , Idoso , Estudos Prospectivos , Adulto , Resultado do Tratamento , Doença da Artéria Coronariana/tratamento farmacológico , Doença da Artéria Coronariana/diagnóstico por imagem
3.
Plant Physiol ; 194(2): 787-804, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-37815230

RESUMO

Root development influences plant responses to environmental conditions, and well-developed rooting enhances plant survival under abiotic stress. However, the molecular and genetic mechanisms underlying root development and abiotic stress tolerance in plants remain unclear. In this study, we identified the MYB transcription factor-encoding gene IbMYB73 by cDNA-amplified fragment length polymorphism and RNA-seq analyses. IbMYB73 expression was greatly suppressed under abiotic stress in the roots of the salt-tolerant sweet potato (Ipomoea batatas) line ND98, and its promoter activity in roots was significantly reduced by abscisic acid (ABA), NaCl, and mannitol treatments. Overexpression of IbMYB73 significantly inhibited adventitious root growth and abiotic stress tolerance, whereas IbMYB73-RNAi plants displayed the opposite pattern. IbMYB73 influenced the transcription of genes involved in the ABA pathway. Furthermore, IbMYB73 formed homodimers and activated the transcription of ABA-responsive protein IbGER5 by binding to an MYB binding sites I motif in its promoter. IbGER5 overexpression significantly inhibited adventitious root growth and abiotic stress tolerance concomitantly with a reduction in ABA content, while IbGER5-RNAi plants showed the opposite effect. Collectively, our results demonstrated that the IbMYB73-IbGER5 module regulates ABA-dependent adventitious root growth and abiotic stress tolerance in sweet potato, which provides candidate genes for the development of elite crop varieties with well-developed root-mediated abiotic stress tolerance.


Assuntos
Ácido Abscísico , Ipomoea batatas , Ácido Abscísico/farmacologia , Ácido Abscísico/metabolismo , Ipomoea batatas/genética , Ipomoea batatas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Estresse Fisiológico/fisiologia , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
4.
Nano Lett ; 24(8): 2643-2651, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38353992

RESUMO

Developing high-performance electromagnetic interference (EMI) shielding materials that are lightweight and flexible and have excellent mechanical properties is an ideal choice for modern integrated electronic devices and microwave protection. Herein, we report the preparation of core-shell polyaniline (PANI)-based nanofiber membranes for EMI shielding through seed polymerization. Electrospinning a PANI solution leads to homogeneously dispersed PANI on the nanofiber surface, with abundant attachment sites for aniline through electrostatic adsorption and hydrogen bonding interaction, allowing PANI to grow on the nanofiber surfaces. This stable core-shell heterostructure provides more interfaces for reflecting and absorbing microwaves. The PANI/PVDF@PANI membranes achieved a shielding efficiency (SE) of 44.7 dB at a thickness of only 1.2 mm, exhibiting an exceptionally high specific EMI shielding effectiveness (SE/t) of 372.5 dB cm-1. Furthermore, the composite membrane exhibits outstanding mechanical stability, durability, air permeability, and moisture permeability, also making it suitable for applications such as EM shielding clothing.

5.
BMC Genomics ; 25(1): 572, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844832

RESUMO

KNOXs, a type of homeobox genes that encode atypical homeobox proteins, play an essential role in the regulation of growth and development, hormonal response, and abiotic stress in plants. However, the KNOX gene family has not been explored in sweet potato. In this study, through sequence alignment, genomic structure analysis, and phylogenetic characterization, 17, 12 and 11 KNOXs in sweet potato (I. batatas, 2n = 6x = 90) and its two diploid relatives I. trifida (2n = 2x = 30) and I. triloba (2n = 2x = 30) were identified. The protein physicochemical properties, chromosome localization, phylogenetic relationships, gene structure, protein interaction network, cis-elements of promoters, tissue-specific expression and expression patterns under hormone treatment and abiotic stresses of these 40 KNOX genes were systematically studied. IbKNOX4, -5, and - 6 were highly expressed in the leaves of the high-yield varieties Longshu9 and Xushu18. IbKNOX3 and IbKNOX8 in Class I were upregulated in initial storage roots compared to fibrous roots. IbKNOXs in Class M were specifically expressed in the stem tip and hardly expressed in other tissues. Moreover, IbKNOX2 and - 6, and their homologous genes were induced by PEG/mannitol and NaCl treatments. The results showed that KNOXs were involved in regulating growth and development, hormone crosstalk and abiotic stress responses between sweet potato and its two diploid relatives. This study provides a comparison of these KNOX genes in sweet potato and its two diploid relatives and a theoretical basis for functional studies.


Assuntos
Diploide , Regulação da Expressão Gênica de Plantas , Ipomoea batatas , Família Multigênica , Filogenia , Proteínas de Plantas , Estresse Fisiológico , Ipomoea batatas/genética , Ipomoea batatas/crescimento & desenvolvimento , Ipomoea batatas/metabolismo , Estresse Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Genoma de Planta , Perfilação da Expressão Gênica , Regiões Promotoras Genéticas
6.
Plant Physiol ; 191(1): 496-514, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36377782

RESUMO

Plant flavonoids are valuable natural antioxidants. Sweet potato (Ipomoea batatas) leaves are rich in flavonoids, regenerate rapidly, and can adapt to harsh environments, making them an ideal material for flavonoid biofortification. Here, we demonstrate that the B-box (BBX) family transcription factor IbBBX29 regulates the flavonoid contents and development of sweet potato leaves. IbBBX29 was highly expressed in sweet potato leaves and significantly induced by auxin (IAA). Overexpression of IbBBX29 contributed to a 21.37%-70.94% increase in leaf biomass, a 12.08%-21.85% increase in IAA levels, and a 31.33%-63.03% increase in flavonoid accumulation in sweet potato, whereas silencing this gene produced opposite effects. Heterologous expression of IbBBX29 in Arabidopsis (Arabidopsis thaliana) led to a dwarfed phenotype, along with enhanced IAA and flavonoid accumulation. RNA-seq analysis revealed that IbBBX29 modulates the expression of genes involved in the IAA signaling and flavonoid biosynthesis pathways. Chromatin immunoprecipitation-quantitative polymerase chain reaction and electrophoretic mobility shift assay indicated that IbBBX29 targets key genes of IAA signaling and flavonoid biosynthesis to activate their expression by binding to specific T/G-boxes in their promoters, especially those adjacent to the transcription start site. Moreover, IbBBX29 physically interacted with developmental and phenylpropanoid biosynthesis-related proteins, such as AGAMOUS-LIKE 21 protein IbAGL21 and MYB308-like protein IbMYB308L. Finally, overexpressing IbBBX29 also increased flavonoid contents in sweet potato storage roots. These findings indicate that IbBBX29 plays a pivotal role in regulating IAA-mediated leaf development and flavonoid biosynthesis in sweet potato and Arabidopsis, providing a candidate gene for flavonoid biofortification in plants.


Assuntos
Arabidopsis , Ipomoea batatas , Ipomoea batatas/genética , Ipomoea batatas/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Flavonoides/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Regulação da Expressão Gênica de Plantas
7.
Anal Bioanal Chem ; 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38358531

RESUMO

α-Glucosidase (α-Glu) is implicated in the progression and pathogenesis of type II diabetes (T2D). In this study, we developed a rapid colorimetric technique using platinum nanoparticles stabilized by chitosan (Ch-PtNPs) to detect α-Glu activity and its inhibitor. The Ch-PtNPs facilitate the conversion of 3,3',5,5'-tetramethylbenzidine (TMB) into oxidized TMB (oxTMB) in the presence of dissolved O2. The catalytic hydrolysis of 2-O-α-D-glucopyranosyl-L-ascorbic acid (AA-2G) by α-Glu produces ascorbic acid (AA), which reduces oxTMB to TMB, leading to the fading of the blue color. However, the presence of α-Glu inhibitors (AGIs) hinders the generation of AA, allowing Ch-PtNPs to re-oxidize colorless TMB back to blue oxTMB. This unique phenomenon enables the colorimetric detection of α-Glu activity and AGIs. The linear range for α-Glu was found to be 0.1-1.0 U mL-1 and the detection limit was 0.026 U mL-1. Additionally, the half-maximal inhibition value (IC50) for acarbose, an α-Glu inhibitor, was calculated to be 0.4769 mM. Excitingly, this sensing platform successfully detected α-Glu activity in human serum samples and effectively screened AGIs. These promising findings highlight the potential application of the proposed strategy in clinical diabetes diagnosis and drug discovery.

8.
BMC Pregnancy Childbirth ; 24(1): 13, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166871

RESUMO

BACKGROUND: Healthy parturients may experience pulmonary edema and disturbed cardiac function during labor. We aimed to evaluate the extravascular lung water (EVLW), intravascular volume, and cardiac function of normal parturients during spontaneous vaginal delivery by bedside ultrasound. And to explore the correlation between EVLW and intravascular volume, cardiac function. METHODS: This was a prospective observational study including 30 singleton-term pregnant women undergoing spontaneous vaginal delivery. Bedside ultrasound was performed at the early labor, the end of the second stage of labor, 2 and 24 h postpartum, and 120 scanning results were recorded. EVLW was evaluated by the echo comet score (ECS) obtained by the 28-rib interspaces technique. Inferior vena cava collapsibility index (IVC-CI), left ventricle ejection fraction, right ventricle fractional area change, left and right ventricular E/A ratio, and left and right ventricular index of myocardial performance (LIMP and RIMP) were measured. Measurements among different time points were compared, and the correlations between ECS and other measurements were analyzed. RESULTS: During the spontaneous vaginal delivery of healthy pregnant women, 2 had a mild EVLW increase at the early labor, 8 at the end of the second stage of labor, 13 at 2 h postpartum, and 4 at 24 h postpartum (P < 0.001). From the early labor to 24 h postpartum, ECS first increased and then decreased, reaching its peak at 2 h postpartum (P < 0.001). IVC-CI first decreased and then increased, reaching its minimum at the end of the second stage of labor (P < 0.001). RIMP exceeded the cut-off value of 0.43 at the end of the second stage of labor. ECS was weakly correlated with IVC-CI (r=-0.373, P < 0.001), LIMP (r = 0.298, P = 0.022) and RIMP (r = 0.211, P = 0.021). CONCLUSIONS: During spontaneous vaginal delivery, the most vital period of perinatal care is between the end of the second stage of labor and 2 h postpartum, because the risk of pulmonary edema is higher and the right ventricle function may decline. IVC-CI can be used to evaluate maternal intravascular volume. The increase in EVLW may be related to the increase in intravascular volume and the decrease in ventricular function.


Assuntos
Água Extravascular Pulmonar , Edema Pulmonar , Feminino , Humanos , Gravidez , Parto Obstétrico , Água Extravascular Pulmonar/diagnóstico por imagem , Edema Pulmonar/diagnóstico por imagem , Edema Pulmonar/etiologia , Volume Sistólico , Ultrassonografia , Estudos Prospectivos
9.
Chem Biodivers ; 21(8): e202400977, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38837616

RESUMO

Two previously uncharacterized compounds, an aconitine-type C19-diterpenoid alkaloid (1) and a napelline-type diterpenoid alkaloid C20-diterpenoid alkaloid (2), as well as ten known compounds (3-12), were isolated from Aconitum pendulum. Their structures were elucidated based on spectroscopic data, including 1D and 2D NMR, IR, HR-ESI-MS, and single-crystal X-ray diffraction analysis. The anti-insecticidal activities of these compounds were evaluated by contact toxicity tests against two-spotted spider mites, and compounds 1, 2, and 9 showed moderate contact toxicity, with LC50 values of 0.86±0.09, 0.95±0.23, and 0.89±0.19 mg/mL, respectively. This study highlights the potential use of diterpenoid alkaloids as natural plant-derived pesticides for the management of plant pests.


Assuntos
Aconitum , Alcaloides , Diterpenos , Aconitum/química , Diterpenos/química , Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Alcaloides/química , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Animais , Tetranychidae/efeitos dos fármacos , Estrutura Molecular , Conformação Molecular , Cristalografia por Raios X , Inseticidas/química , Inseticidas/isolamento & purificação , Inseticidas/farmacologia , Modelos Moleculares
10.
Mikrochim Acta ; 191(8): 488, 2024 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-39066796

RESUMO

Hydroxyl radical (·OH) scavenging capacity (HOSC) estimation is essential for evaluating antioxidants, natural extracts, or drugs against clinical diseases. While nanozymes offer advantages in related applications, they still face limitations in activity and selectivity. In response, this work showcases the fabrication of laminarin-modulated osmium (laminarin-Os) nanoclusters (1.45 ± 0.05 nm), functioning as peroxidase-like nanozymes within a colorimetric assay tailored for rational HOSC estimation. This study validates both the characterization and remarkable stability of laminarin-Os. By leveraging the abundant surface negative charges of laminarin-Os and the surface hydroxyls of laminarin, oxidation reactions are facilitated, augmenting laminarin-Os's affinity for 3,3',5,5'-tetramethylbenzidine (TMB) (KM = 0.04 mM). This enables the laminarin-Os-based colorimetric assay to respond to ·OH more effectively than citrate-, albumin-, or other polysaccharides-based Os. In addition, experimental results also validate the selective peroxidase-like behavior of laminarin-Os under acidic conditions. Antioxidants like ascorbic acid, glutathione, tannic acid, and cysteine inhibit absorbance at 652 nm in the colorimetric platform using laminarin-Os's peroxidase-like activity. Compared with commercial kits, this assay demonstrates superior sensitivity (e.g., responds to ascorbic acid 0.01-0.075 mM, glutathione 1-15 µg/mL, tannic acid 0.5-5 µM, and monoammonium glycyrrhizinate cysteine 1.06-10.63 µM) and HOSC testing for glutathione, tannic acid, and monoammonium glycyrrhizinate cysteine. Overall, this study introduces a novel Os nanozyme with exceptional TMB affinity and ·OH selectivity, paving the way for HOSC estimation in biomedical research, pharmaceutical analysis, drug quality control, and beyond.


Assuntos
Benzidinas , Sequestradores de Radicais Livres , Glucanos , Radical Hidroxila , Osmio , Benzidinas/química , Colorimetria/métodos , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Glucanos/química , Radical Hidroxila/química , Radical Hidroxila/análise , Osmio/química , Oxirredução , Peroxidase/química , Peroxidase/metabolismo
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